interior angle

American  

noun

Geometry.

1. an angle formed between parallel lines by a third line that intersects them.

2. an angle formed within a polygon by two adjacent sides.

---

interior angle British  

noun

1. an angle of a polygon contained between two adjacent sides

2. any of the four angles made by a transversal that lie inside the region between the two intersected lines

---

interior angle Scientific  

/ ĭn-tîr′ē-ər /

1. Any of the four angles formed inside two straight lines when these lines are intersected by a third straight line.

2. An angle formed by two adjacent sides of a polygon and included within the polygon.

3. Compare exterior angle

---

Etymology

Origin of interior angle

First recorded in 1750–60

Example Sentences

Each interior angle of a regular heptagon is a bit over 128 degrees, so when we put three of them together at a vertex, we get more than 360 degrees.

From Scientific American • Nov. 17, 2013

I got the first cut, but again, when I started cutting the interior angle, the bar worked its way out of the jig, and the tool dug in and broke.

From "October Sky" by Homer Hickam

Hind wings with the interior angle prominent, acute.

From Journal of the Proceedings of the Linnean Society - Vol. 3 Zoology by Various

Fasten the bottom to the front by means of a thin block glued into the interior angle between the under side of the bottom and the back side of the front.

From Handwork in Wood by Noyes, William

Its oldest form resembled an English V with a straight line running up bisecting its interior angle.

From A Plain Introduction to the Criticism of the New Testament, Vol. I. by Scrivener, Frederick Henry Ambrose